1. Field of the Invention
This invention relates to a flat laminated sheet for being folded into a mailer with a transparent window, and more particularly to providing such a sheet in a form which can be fed reliably through printing and folding devices.
2. Description of the Prior Art
A number of different types of mailer blanks are used to provide mailers after suitable printing and folding operations. A typical mailer, after the printing operations are completed, includes at least some variable information, such as the address of the individual to whom the mailer will be sent. The mailer may also have fixed information, which is applied in an identical manner to a large number of mailers.
It is often particularly desirable to print the address to which the mailer is being sent, along with other variable information as needed, on a part of the mailer blank which becomes the inside of an envelope structure after the folding processes are completed. Often, a transparent window is provided on a part of the mailer blank through which a portion of the printed information can be viewed after the printing and folding processes are completed. Such a window is conventionally formed by adhesively attaching a transparent sheet of plastic or cellulose material to extend across an aperture which has been die cut in the sheet of paper forming the mailer blank. By properly aligning the printing, the address information can be read through the transparent window positioned opposite to the address information after folding. In this way, it becomes unnecessary to print variable information on both sides of the mailer blank; rather, all such information is printed on the surface which becomes the inside of the envelope structure, thereby saving a printing step.
For example, when a mailer of the type just described is used to distribute checks, the name and address of the recipient may be visible both as the location to which the mailer is addressed and as the payee of the check. Upon receipt, the envelope is opened and the check portion is separated from the remaining portion of the mailer by tearing along a perforated line. Other variable information, such as the amount of the check and account numbers is printed on the same side of the mailer blank as the check, but is concealed when mailer is folded for mailing.
U.S. Pat. No. 4,951,864 to Dicker describes apparatus a typical prior art mailer blank and the folding and sealing thereof. Dicker's mailer blank includes remoistenable glue strips on the longitudinal sides and one traverse side of the blank, which strips are moistened prior to folding into a mailer envelope. A window aperture shown within the mailer is formed by adhesively attaching a transparent sheet to extend across a rectangular opening in the paper of the mailer. However, the transparent sheet overlaps the opening, being adhesively attached to the paper around the opening, causing the localized increase in thickness.
A particular problem with a conventional mailer blank of the type described above arises. as a result of the additional thickness of the transparent sheet used to form the window. A typical mailer blank is made from 0.004 inches thick paper stock and 0.001 inch thick transparent sheet attached by an adhesive around an aperture in the paper stock. Thus, around the edges of the aperture, where the paper stock and the transparent sheet overlap, the thickness of the mailer blank is increased by 0.001 inch, or 25 percent of the paper thickness. Because of this difference in thickness, the mailer blanks do not lie flat when they are stacked for feeding into the, apparatus used for the printing and folding apparatus. They further do not lie flat when stored as inventory or shipped from the point of manufacture to the end user's facilities. Even if shims are used in packing, the mailer blanks generally have a permanent curl when they are removed from the cartons in which they are shipped and stored.
More recently, it has become common practice for a company such as an insurance company or other organization, to provide an identification card (Id card) to an individual wherein the ID card bears a particular identification number, e.g., a membership or account number, that can be used in storing or retrieving a computerized record relating to that individual. These ID cards are typically manufactured in bulk, pre-printed, and inserted into a mailing envelope.
Moreover, this previous method of providing an ID card increases the number of steps involved in producing individualized mailers. Specifically, the address or other information provided on the mailer must be printed separately from the ID card. The ID card must then be inserted into the mailer, which involves yet another step. This can also result in mismatches between the mailer confirmation and the ID card information that may cause loss of further time and effort in correcting the error.
Mailers for high volume applications are preferably printed and subsequently folded in high speed devices having an input capacity of, for example, 2000 sheets. However, due to the difference in thickness abound the window aperture, a stack of 2000 sheets of mailer blanks manufactured as described above is typically about twelve inches thick around the aperture and about eight inches thick at locations remote from the aperture, such as the edge of the form being fed into the printing and folding devices. Furthermore, these sheets cannot lie flat an any bin holding them in quantities of about 2000 for feeding into a printing or folding device.
The various mechanisms used to feed sheets one at a time through printing and folding devices are very intolerant of curled sheets, particularly if the curl results in the corners of an individual sheet being raised or lowered with respect to the central part of the sheet. Specifically, the curl prevents individual sheets from being properly separated in the mechanisms designed to separate the sheets so that they can be fed one at a time for printing or folding. In addition, the curl causes the corners of the sheets to be caught on various obstructions along the paper feeding path of the printing and folding devices. In this way, failures to feed sheets and various types of paper jams are caused as the equipment is operated.
A further problem is realized by use of separately printed and inserted ID cards. Specifically, a high speed printer/folder device cannot be utilized efficiently with these cards because they will either jam a form feeder or will need to be adhered prior to the mailer being automatically folded.
These problems have become more serious with an increased use of non-impact printers, such as laser printers, to print the variable information on mailers, since such printers require the rapid and reliable feeding of individual sheets of paper into the printing process.
Attempts have been made to eliminate the need for a second transparent sheet by treating a section of the paper form so that the paper becomes transparent in a particular window area. For example, the See Thru Paper.TM. Window, Form #9644, manufactured by Standard Register, is described in U.S. Pat. No. 5,418,205. However, the transparency of the window area is actually only "translucent", which can pose problems for automated mail reading devices.
What is needed is a mailer blank having an aperture with a transparent window, without the increased local thickness resulting in paper curl when significant numbers of the blanks forms are stacked.
What is also needed is a mailer blank which does not require separate printing and adherence of an identification card so that printing and folding can be efficiently carried out on an automated device.